1. Field of the Invention
This invention is directed to measuring the effects of artificial sweeteners on the enzyme kinetics of biological systems.
2. Summary of the Prior Art
A. Breakdown of Sugar Essential to Proper Absorption.
Natural sugar in the human diet is made up mostly of sucrose. Furthermore there is a significant increase in the sugar consumption via carbonated soft drinks and energy drinks sweetened with sources of sucrose (including high fructose corn syrup). Sucrose, a disaccharide is not directly digestible. As a first step towards absorption and metabolism, sucrose is enzymatically cleaved to produce monosaccharides so that it can be processed by the intestine. This is the most important step in the process of calorie intake and the downstream process of glucose metabolism.
The enzymatic conversion of sucrose to glucose and fructose follows the classic Michaelis-Menten mechanism, one of the most important enzymatic reactions from yeast to humans. Enzymes catalyze biochemical reactions, speeding up the conversion from substrate to product molecules, which can pass through the intestinal wall and be absorbed by the body. When enzymatic reactions are altered in the very first step of calorie intake, it is expected that rest of the downstream process involving glucose metabolism will also be affected.
B. Natural Artificial Sweeteners (NAS)
Non-caloric artificial sweeteners (NAS), introduced over a century ago provide the sweet taste to foods without adding any calories and is used as a substitute for natural sugars. Currently, there are six different NAS products for use in the United States that are approved by the US Food and Drug Administration: saccharin, aspartame, acesulfame potassium (Ace-K), sucralose, neotame, and advantame (FDA 2015). NAS are regulated as a food additive, unless its use is generally recognized as safe (GRAS). Currently, GRAS notices are pending for two other NAS, steviol glycosides obtained from the leaves of the stevia plant and Siraitia grosvenorii Swingle fruit (monk fruit).
The broader rationale for the wide-spread use of NAS is due to the argument that they can pass through the gastrointestinal tract without being digested. More importantly, it is generally believed that NAS are healthy substitutes for sugars because they provide sweet taste without calories or glycemic effects. Though studies conducted in human subjects with and without diabetes did not affect clinical measures of glucose metabolism (blood glucose level, C-peptide and HBA1c concentration) (Nehrling, Kobe et al. 1985, Corless, Gonnet et al. 1996, Mezitis, Maggio et al. 1996, Baird, Shephard et al. 2000), several epidemiological studies found that negative health effects towards metabolic syndrome, weight gain and type-2 diabetes (Ludwig, Peterson et al. 2001, Dhingra, Sullivan et al. 2007, Fowler, Williams et al. 2008, Lutsey, Steffen et al. 2008, Swithers, Martin et al. 2010, de Koning, Malik et al. 2011, Fagherazzi, Vilier et al. 2013, Swithers 2013).
C. Health Effects
NAS are not physiologically inert and the manner in which they affect the biological process starts from the first step; how sucrose is converted into glucose and fructose. Therefore there is a critical need of a method that can determine how the rate of conversion of sucrose is affected in the presence of NAS. This step is integral to investigate the potential mechanism of energy and glucose homeostasis as well as on metabolic response to an oral glucose load.